Tata offers the Curvv with a choice of powertrains: a 120hp 1.2-litre turbo-petrol, a 118hp 1.5-litre diesel, and an all-new 125hp GDI (Gasoline Direct Injection) turbo-petrol engine. Each comes with a 6-speed manual or a 7-speed dual-clutch automatic transmission. We tested the diesel-automatic and the new GDI turbo-petrol-manual variants to evaluate their real-world efficiency.
- Both versions get three drive modes: Eco, City and Sports
- The diesel’s dual-clutch auto is tuned for efficiency
- The GDI Turbo-petrol’s tall gearing affects drivability
In our city loop, the diesel-automatic version delivered 11.15kpl, while the GDI turbo-petrol with a 6-speed manual gearbox returned 8.40kpl under the same conditions. On the highway, the diesel-automatic impressed with 17.23kpl, while the GDI turbo-petrol manual delivered 12.77kpl.
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While neither variant gets an auto engine stop-start feature to keep a check on fuel consumption while idling, both have an Eco mode, which significantly dulls down the engine’s responsiveness in the interest of efficiency. The diesel-automatic uses a dual-clutch transmission, but it felt a bit jerky at low speeds, and the shifts weren’t very seamless.
The GDI turbo-petrol delivers its performance only beyond 1800 rpm, and this characteristic, combined with the six-speed manual's tall gearing, requires frequent downshifts in city driving. Throttle response, even in its economy setting, is quite sensitive, often resulting in a jerky on-and-off throttle behaviour.
While cruising at 100kph, the diesel spins at 1800rpm in seventh gear, whereas the GDI turbo-petrol is at 2200rpm in sixth gear.
Autocar India’s fuel efficiency testing
Before our real-world fuel efficiency tests, we fill our test cars’ tanks to the brim and maintain tyre pressures based on the manufacturer’s recommendation. These cars are driven on fixed city and highway loops in and around Navi Mumbai, maintaining certain average speeds. Throughout the tests, there is only one person in each car who runs the aircon and other electricals, such as the audio system, indicators and wipers, when required, just like a regular user would. Periodic driver swaps further neutralise variations in driver patterns. At the end of each cycle, we calculate efficiency by refilling the tanks to full.
